Hidden features of Bash

bash shell scripting hidden-features
Patrick picture Patrick · Oct 17, 2008 · Viewed 39.8k times · Source

Shell scripts are often used as glue, for automation and simple one-off tasks. What are some of your favorite "hidden" features of the Bash shell/scripting language?

  • One feature per answer
  • Give an example and short description of the feature, not just a link to documentation
  • Label the feature using bold title as the first line

See also:

Answer

chillitom picture chillitom · Feb 25, 2009

insert preceding line's final parameter

alt-. the most useful key combination ever, try it and see, for some reason no one knows about this one.

press it again and again to select older last parameters.

great when you want to do something else to something you used just a moment ago.

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